The field of the disclosure relates generally to power generation systems, and, more particularly, to a solid oxide fuel cell-based power generation system and an associated power delivery system.
Fuel cells are electrochemical energy conversion devices that have demonstrated a potential for relatively high efficiency and low pollution in power generation. A fuel cell generally provides direct current (DC) power which may be converted to alternating current (AC) power through, e.g., an inverter. The DC power or AC power can be used to power motors, lights, and any number of electrical devices and systems. Certain fuel cells, such as solid oxide fuel cells (SOFCs), may operate in large-scale power systems that provide electricity to satisfy industrial and municipal needs.
A fuel cell produces electricity by electrochemically combining a fuel and an oxidant across an ionic conducting layer. Fuel cells are typically amassed in electrical series in an assembly of fuel cells to produce power at useful voltages or currents. In general, components of a fuel cell include the electrolyte and two electrodes, i.e., an anode and a cathode. The reactions that produce electricity generally take place at the electrodes. The electrolyte carries electrically charged particles from one electrode to the other. Typically, the fuel cells convert hydrogen (fuel) and oxygen (oxidant) into water (byproduct) to generate DC electric power. The water byproduct may exit the fuel cell as steam in high-temperature operations. This discharged steam (and other hot exhaust components) may be utilized in turbines and other applications to generate additional electric power, typically AC power, thereby providing increased efficiency of power generation.
In at least some known power generation systems for industrial facilities, all of the DC power is inverted into AC power and combined with AC power generated by the secondary power generation process. In addition, AC power from the power grid may be used either as a full-time support power source or an occasional backup power source. The combined AC power is then distributed throughout the industrial facility. For critical process applications requiring reliable sources of DC power, a portion of the combined AC power is typically converted to DC power through a multi-stage conversion process. This multi-stage conversion process often includes integrated uninterruptable power supply technology and DC voltage conditioning. Such multiple conversion stages increase system losses, reduce system reliability, and require extensive cooling provisions. Also, such installations require substantial capital expenditures for construction and operations and maintenance (O&M) expenditures for preventative and corrective maintenance.